Koalas may look like peaceful, eucalyptus-chewing tree-dwellers, while the marsupial lion was one of the fiercest Ice Age predators ever to roam Australia.
But scientists have now discovered that these two very different animals share a surprising family connection.
For the first time, researchers have uncovered molecular evidence linking several extinct Australian megafauna species to their modern relatives, offering a clearer picture of the continent’s ancient animal family tree.
The study, published in Proceedings of the Royal Society B: Biological Sciences, was led by Dr. Michael Buckley from The University of Manchester.
His team used an advanced technique called zooarchaeology by mass spectrometry, or ZooMS, often described as “collagen fingerprinting.”
Collagen is a tough protein found in bones, and unlike DNA, it can survive for hundreds of thousands of years—even in Australia’s warm climate, where DNA breaks down too quickly to be useful.
Dr. Buckley and his colleagues analyzed 51 fossilized marsupial bones collected from caves and swamps in Tasmania.
These fossils were more than 100,000 years old, far older than the reach of traditional DNA testing. Because collagen proteins remain intact much longer, they allowed the team to identify not just the species of the fossils, but also how they were related to living marsupials.
One of the most unexpected findings was that koalas and the extinct marsupial lion shared a common ancestor 25–35 million years ago.
The marsupial lion, formally known as Thylacoleo carnifex, was a powerful predator roughly the size of a leopard.
Despite the dramatic differences between the gentle koala and this fierce hunter, the new evidence places them closer together on the evolutionary tree than scientists previously believed.
The researchers also uncovered new information about two other extinct species: Zygomaturus trilobus, a large browsing herbivore, and Palorchestes azael, an unusual long-nosed marsupial sometimes compared to a “marsupial tapir.”
By analyzing their collagen sequences, the team confirmed that both belonged to the same larger group as koalas and wombats, known as Vombatiformes.
These discoveries could help scientists better understand why Australia lost nearly 90% of its giant land animals during the Late Pleistocene. This extinction event remains one of the great mysteries of the ancient world, with ongoing debates about whether climate change, human hunting, or a mix of both drove these species to disappear.
Because ZooMS can identify species from even tiny bone fragments, it offers a powerful tool for building more accurate timelines of when these megafauna lived and how long they overlapped with early humans. Dr. Buckley believes this method could transform the study of extinct animals by allowing thousands of fossils to be analyzed quickly and efficiently.
This research shows that even after tens of thousands of years, the bones of ancient animals can still reveal surprising stories—connecting Australia’s living wildlife to long-lost giants of the Ice Age.
Source: University of Manchester.
